Research on Online Monitoring Technology of Low-Voltage Spark Discharge Phenomenon in Cable Metal Sheath

During a cable operation and maintenance process, a rare phenomenon of low-voltage discharge from the cable sheath was observed onsite. To investigate the cause and provide detection methods for maintenance, researchers speculated on the discharge principle and set up a three-phase interconnected cable test circuit in the laboratory to simulate actual operating conditions. The test results successfully replicated the discharge phenomenon. Based on the characteristics of this type of discharge signal, further research was conducted on its online monitoring technology. Under simulated actual operating conditions, the frequency domain characteristics and noise characteristics of the signal were analyzed, and the optimal configuration parameters for wavelet transform denoising were studied. This further supplemented the methods and techniques for cable operation and maintenance to ensure the safe and stable operation of the cable system.